Intercommunicating system



Sept- 1- R. T. FlTzPA RlcK 2,254,736

Il XTERCOMMUNICATING SYSTEM Filed Feb. 14, 1940 STAT/pal No.2.

4 I ATTORN Y.

Patented Sept. 2,

STATES PATENT OEFIC nami- 2,254,736 rNrEacoMMUNIoATING SYSTEM Richard'1'. Fitzpatrick, Detroit, Mich., assignor to Wilbert I. Rudolph,Detroit, Mich.

12 Claims.

My invention relates to a new and useful improvement in anIntercommunicating System embodying a plurality of sound units each ofwhich may selectively be used either as a dynamic speaker or as atransmitter, these sound units being positioned at spaced locationswhich may be termed stations. At each station there is provided aselector mechanism whereby the sound unit of that station may be broughtinto cooperative relation with the sound unit of any desired unit in theinstallation. At each station there is also provided a control switch,the operation of which serves to selectively alternate the sound unitswhich have been brought into cooperative relation into eithertransmitters or speakers. In intercommunication systems the commonmethod of installation is the mounting of a number of sound units atseparate stations with a control at one of the stations which is termeda master station. In such installations the control of the systemresides in any one station and the alternating of the sound units fromspeaking connection to listening connection, and vice versa, may beeffected only from the master station.

It is an object of the present invention to provide anintercommunicating system in which controls will be located at each ofthe stations so that a person at any one of the stations may, by propermanipulation of the controls, connect to any of the other stations inthe unit and alternate the sound unit so connected to serve either asdynamic speakers or as transmitters.

In intercommunicating systems where it is desired to provide completeintercommunication between the various stations as outlined above, it isquite common to use an amplifier for each station and in suchinstallations it is generally customary to run the input and outputwires up to the master stations where they are switched at that point.Even where a single amplifier is used and a single control station isused, the input and output wires are run up to the master station andswitched at that point. It is an object of the present invention toprovide an intercommunication system having a single amplifier and soarranged and constructed as to eliminate the necessity of running inputand output wires up to the master stations.

It is another object of the invention in an intercommunication system ofthis type for eliminating the parasitic oscillation arising from theproximity of the input and the output Wires.

It is another object of the invention to provide in anintercommunicating system a means whereby the stations may beselectively alternated from the listening to the talking position,thereby changing the selected speaker from the input to the output ofthe amplifier and oppositely effecting the speaker at the master stationused, that is changed over from dynamic speakers to transmitters, at adistant point through the operation, at the station, of the necessaryconrols for operating a relay or magnetically controlled switch at adistant point.

It is another object of the invention to provide a construction in whichthere is no interruption at the individual speakers resulting from theshifting from the listening position to the talk position, or viceversa.

Another object of the invention is the provision in anintercommunicating system of this type of a construction whereby theoutput is grounded out in the interval between the changeover so thatthe change-over from listening to the talk position, and vice versa, oftwo interconnected stations is actually made when the output is groundedout so as to remove capacity in the line and extraneous noises in thespeakers.

Another object of the invention is the provision of a novel system ofwiring and controls in an installation of this type whereby the variousadvantages referred to may be obtained and the various disadvantagescommonly found in intercommunicating systems avoided.

Another object of the invention is the provision of anintercommunicating system of this type so arranged and constructed thatit may be compact, highly efficient in use, easily and quicklyinstalled, and economically manufactured and installed.

Other objects will appear hereinafter.

It is recognized that various changes and modifications may be made inthe specific details of structure illustrated without departing from thespirit of the invention and it is desired that such variations andmodifications shall be embraced within the scope of this invention.

Forming a part of this specification is a drawing which is adiagrammatic View illustrating the installation.

At each of the stations there is a talk-listen switch and a selectorswitchas Well as a sound unit which may be used either as a dynamicspeaker or a transmitter. In this system there is also used an amplifier44 having the common three-station installation illustrated, isconnected on one side to the common wire 45. The speaker 9 at stationNo. 1 is connected to the common wire 45 by means of the wire 46 and thewire 41. One side of the speaker ill at station No. 2 is connected tothe common wire 45 by the wire 48. One side of the speaker II at stationNo. 3 is connected to the common wire 45 by the wire 49. v

The other side of the speaker 9 at station No. 1 is connected by thewire 50, at the'relay or solenoid mechanism A, to the switch blade 5!and to the switch blade 52 at the relay or solenoid A. The other side ofthe speaking unit. H] at station No. 2 is connected by the wire 53 tothe switch blade 54 at the relay or solenoid mechanism B and to theswitch blade 55 at the solenoid mechanism or relay B. The opposite sideof the speaker I! is connected by the wire 56- to the switch blade 51 ofthe relay or electric magnetic mechanism C and to the switch blade 58 ofthe relay or electric magnetic mechanism C. The blade 5|, the blade 54'and the blade 57 are connected by the wire 59 to the flexible contact60.

At each of the relay mechanisms there is provided a hinged plate (Hwhich is normally swung outwardly as shown in the drawing. Each of theseplates carries a rocker arm 62 so arranged and constructed that when theplate BI is swung inwardly, this rocker arm 62 will swing upwardly andforce the lower switch blade against the upper switch blade. Forinstance, at the relay A, the plate 6| overlies the core 63 of theelectromagnet and when the coil is energized the plate 6! will swingupwardly to bring the switch blades 5! and 51 into engagement to make acircuit. The same method of operation takes place at all of the otherrelays illustrated and described.

The lower blades 52 and 55. and 58' at the relays A, B and C areconnected by the wire 64 to the blades 65 and 66.

The input wire 41 is connected to stationary flexible contact blades 67and 58. The output wire 46 is connected to the stationary flexiblecontacts 69 and a flexible contact blade 18. A flexible contact blade His grounded through the wire 72 to which also connects the common wire45. These flexible blades 66, H, 6!), "l and 65 are connected at one oftheir ends to a slidable block of insulation 73 which is slidable in onedirection by a rocker arm 74 and in the other direction by a rocker arm15, the rocker arm 14 projecting outwardly from a swingable plate 16associated with the solenoid or relay L and the rocker arm i projectingoutwardly from the swingable plate Tl asociated with the solenoid orrelay T,

The construction is such that when the coil of the solenoid L isenergized, the plate 16 will be drawn inwardly so as to rock the arm 14.downwardly and slide the bar 13 downwardly. When the coil of thesolenoid T is energized, the plate I! will be swung inwardly to rock thearm to force the member 13 upwardly. The contacts 78 and 19 areconnected together by the wire, 80. A battery Si or other suitablesource of electrical energy is provided and one side of this battery isconnected by the wire 82 to one side of the coil or solenoid L and alsoby the wire 82 and the wire 83 to one side of the coil of the solenoid TThis wire 82 also serves to connect the same side of the battery to oneside of each of the coils A, A, B, B, C, and C. The opposite side of thebattery is connected by the wire 84' to the common wire 45.

At each of the stations the control switch embodies rotatable contactarms l5, l6 and I! which rotate in unison when manually operated.Contacts 53 and M are provided at each switch, the contact !4 being thelisten contact and the contact l3 being the talk contact. The commonwire is connected by the wire 24 to an arcuate metallic plate 23 and thearm I5 is adapted to ride on the plate 23 in contact therewith so thatwhen the arm I5 is brought into engagement with the listen contact 14,this listen contact I4 is thereby connected to the common wire 45.Similarly, when the arm I5 is rotated to engage the contact I3, thiscontact is connected through the wiring illustrated to the common. Whenthe arm l5 engages the contact M, the relay L is energized, the commonbeing connected to the wire 83 since this wire 88 is connected throughsuitable wiring to the contact M at each of the stations.

For each of the stations there is provided apair of electric magneticswitches or relays A and A corresponding to station No. l, B and Bcorresponding to station No. 2, and C and C corresponding to. stationNo. 3.

When the arm 15 at any of the stations is moved to engage the contact I4or the contact l3, the relay A, B, C, depending upon which station isbeing operated, will be energized so that these relays may be termed thestation relays in. that through these relays the operator is able to beon the output, which is the listening position of the station beingoperated, when contact i4 is engaged and vice versa when contact I3 isengaged.

The selector switch, which is positioned at each of the stations, isprovided with a metallic ring 33. which is connected by the wire 21 tothe common. In the drawing I have illustrated at eachor" the stations,contacts I, 2 and 3 which may be engaged by the rotating arm 28 whichrides over the metallic ring 38 and serves to establish electricalconnection between the contact I, 2 or 3 whichever has been engaged withthe metallic ring 38. It will be noted that at the station No. 1 thecontact l, at station No 2 the contact 2, and at station No. 3 thecontact 3 is not connected by any wiring as this contact corresponds tothe station at which the switch is located.

In operation, when the arm I5 is in engagement with either the contacts[4 or l3- and the arm 28; is in engagement with a selector contact I, 2or 3, corresponding to a different station, the coil A, B or Ccorresponding to the station selected will be energized and, thus, thespeaker at the station selected will be electrically connected throughthe switch at the coil A, B or C which has been energized and the wire9| to the contact 60. When the coil L is energized, that is when theoperator at the controlling station desires to listen, the

contact will be electrically connected through.

engagement with the contact 68 to the input. of the amplifier permittingthe person at the selected station to talk through the speaker at thatstation.

When the coil T'is energized, that is when the person at the operationstation desires to talk, the contact Bi] will be electrically connectedthrough engagement with the contact 69 with the output of the amplifien.At the same time, the speaker at the operating station will beconnected' through the coil A, B or C, as the case may be, with thecontact. V or the contact 66. When the coil L is energized, that is,when the person at the operating station desires to listen,

the contact 65 would be connected through engagement with the contactI85 with the output of the amplifier. When the coil T is energized, thatis, when the person at the operating station desires to talk, a contact65 would be moved away from the contact I65 and the contact 65 would bebrought into engagement with the contact 61, therebyconnecting thespeaker at the operating station with the input of the amplifier.

It will be noted that in passing from the output to the input, theoutput is always grounded out and remains grounded out until contactwith the input has been made.

The coils A, B and C are energized by the closing of the talk-listenswitch at their own station. The coils A, B and C are energized throughthe closing of their corresponding switch in the selector mechanism of astation other than the station to which they relate. Thus, when thetalk-listen switch at station No. 1 is moved to engage either thecontacts l3 or M, the coil A is energized and remains energized evenduring the time the arm I5 is being moved from engagement with contactl3 or I4 into engagement with the other contact. The coil A is energizedwhen the arm 28, at some station other than station No. 1, is moved toengage the contact I at that station, provided the talk-listen switchhas been brought into engagement with either the contact l3 or M.

In the operation of the mechanism the selector arm 28 would be moved toengage the contact corresponding to the station selected. For instance,in the drawingillustrated, the arm 28 at station No. 3 has been moved toengage contact I corresponding to station No. 1. When the talk-listenswitch is then moved to engage either the contact [4 or I3, the coil Cwould be energized as would, likewise, the coil A and these coils wouldremain energized so long as the talk-listen switch was engaging eithercontact l3 or M, or moving from engagement with one into engagement withthe other. When in engagement with contact It, the coil L would beengaged and when the arm l5 would be moved into engagement with thecontact l3, the coil T would be energized.

Thus, I have provided a simple and compact structure whereby theoperator at any one of the stations has control of the system and mayconnect himself to any other station in the system and either talk fromhis station or listen, as he desires. Under such conditions thetalklisten switch at the station selected would not be manipulated, norwould the selector at the station selected be manipulated. By groundingout in the manner indicated, all of the disadvantages referred to inregard to building up capacity would be avoided and a simple andefiective structure for the purposes intended is thus provided.

What I claim as new is: v

1. In a communication system of the class described, a plurality ofspeaking units located at separated points; a selector switch for eachof said units operable for establishing electrical connection betweensaid unit and any of said other units, individually, selectively; arelay switch for each of said units, the relay switch of the selectedunit being energized upon operation of a selector switch for selectingthe unit; a talk-listen switch for each of said units movable to closedposition, talking position and listening position, the circuit to saidrelay switches being energized upon movement of said talk-listen switchto either of said positions; a second relay for each of said units, therelay for each of said units being energized upon movement of thetalk-listen switch of said unit to either of said positions; and meansfor maintaining said firstnamed relay energized upon movement of thetalk-listen switch from any of said positions to the other.

2. In a communication system of the class described, a plurality ofspeaking units located at separated points; a selector switch for eachof said units operable for establishing electrical connection betweensaid unit and any of said other units, individually, selectively; arelay switch for each of saidunits, the relay switch of the selectedunit being energized upon operation of a selector switch for selectingthe unit; a talk-listen switch for each of said units movable to closedposition, talking position and listening position, the circuit to saidrelay switches being energized upon movement of said talk-listen switchto either of said positions; a second relay for each of said units, therelay for each of said units being energized upon movement of thetalk-listenswitch of said unit to either of said positions; means formaintaining said firstnamed relay energized upon movement of thetalk-listen switch from any of said positions to the other; an amplifierhaving an input and an output; and means for connecting the output tothe speaking unit at which the talk-listen switch is operated to thelisten position and, simultaneously, connecting the speaking unitselected to the input.

3. In a communication system of the class described, a plurality ofspeaking units located at separated points; a selector switch for eachof said units operable for establishing electrical connection betweensaid unit and any of said other units, individually, selectively; arelay switch for each of said units, the relay switch of the selectedunit being energized upon operation of a selector switch for selectingthe unit; a talklisten switch for each of said units movable to closedposition, talking position and listening position, the circuit to saidrelay switches being energized upon movement of said talk-listen switchto either of said positions; a second relay for each of said units, therelay for each of said units being energized upon movement of thetalk-listen switch of said unit to either of said positions; means formaintaining said firstnamed relay energized upon movement of thetalk-listen switch from any of said positions to the other; an amplifierhaving an input and an output; means for connecting the output to thespeaking unit at which the talk-listen switch is operated to the listenposition and, simultaneously, connecting the speaking unit selected tothe input, and vice versa' upon movement of the operated talk-listenswitch to the talking position from the listening position.

4. In a communication system of the class described, a plurality ofspeaking units located at separated points; a selector switch for eachof said units operable for establishing electrical connection betweensaid unit and any of said other units, individually, selectively; arelay switch for each of said units, the relay switch of the selectedunit being energized upon operation of a selector switch for selectingthe unit; a talk-listen switch for each of said units movable to closedposition, talking position and listening position, the circuit to saidrelay switches being energized upon movement of said talklisten switchto either of said positions; a second relay for each of said units, therelay 'for each of said units being energized upon movement of thetalk-listen switch of said units to either of said positions; means formaintaining said first-named relay energized upon movement of thetalk-listen switch from any of said positions to the other; an amplifierhaving an input and an output; means for connecting the output to thespeaking unit at which the talk-listen switch is operated to the listenposition and, simultaneously, connecting the speaking unit selected tothe input, and vice versa upon movement'of the operated talk-listenswitch to the talking position from the listening position; and means.for grounding out the output in passing from output connection to inputconnectionand maintaining such grounding out until the inputisconnected.

5. In a communication system of the class described, a plurality ofspeaking units positioned at spaced locations; a selector switch foreach of said units for selectively connecting said unit to another ofsaid units selected; a talk-listen switch at each of said units movableto closed position, talk position, and listen position; an amplifierhaving an input and an output; and a plurality of relays operable uponmovement of said talk-listen switch to talk position for connecting theunit at which the switch operated is located to the input of theamplifier and the selected speaking unit to the output of the amplifier.

6. In a communication system of the class described, a plurality ofspeaking units positioned at spaced locations; a selector switch foreach of said units for selectively connecting said unit to another ofsaid units selected; a talkllsten switch at each of said units movableto closed position, talk position and listen position; an amplifierhaving an input and an output; and a plurality of relays operable uponmovement of said talk-listen switch to talk position' for conecting theunit at which the switch operated is located to the input. of theamplifier and the selected speaking unit to the 'output of theamplifier, and vice versa upon movement of the operated switch to listenposition.

7. In a communication system of the class described, a plurality ofspeaking units positioned at spaced locations; a selector switch foreach of said units for selectively connectingsaid unit to another ofsaid units selected; a talklisten switch at each of said units movableto closed position, talk position and listen position; an amplifierhaving an input and an output; and a plurality of relays operable uponmovement of said talk-listen switch to talk position for connecting theunit at which the switch operated is located to the input of. theamplifier and the selected speaking unit to the output of the amplifier,and vice versa upon movement of the operated switch to listen position;and means for grounding out the output in passing from output to input.

8. In a communication system of the class described, a plurality ofspeaking units positioned at spaced locations; a selector switch foreach of said units for selectively connecting said unit to another ofsaid units selected; a talk-listen switch at each of said units movableto closed position, talk position and listen postion; an amplifierhaving an input and an output; a plurality of relays operable uponmovement of said talk-listen switch to talk position for connecting theunit at which the switch operated is located to the input of theamplifier and the selected speaking unit to the output of the amplifier,and vice versa upon movement of the operated switch to listen position;and means for grounding out the output in passing from output to input,and maintaining such grounding out until the input is connected to thespeaking unit previously connected to the output.

9. In a communication system of the class described a plurality ofdynamic speaking units positioned at spaced locations; a selector switchfor each of said units for selectively establishing connection betweensaid unit and another selected unit; a talk-listen switch for each ofsaid units movable to closed position, to talk position and to listenposition; electric circuits connecting said units; a relay switch foreach of said units energized upon the movement of the talk-listen switchof the unit corresponding thereto to closed, talk or listen position; arelay switch interposed in the circuit for each of said units energizedupon the movement of a selector switch at any unit to position forselecting the unit corresponding to said relay switch; an amplifierhaving an input and an output; a pair of relays, said relays beingoperable for establishing communication of a speaking unit at which thetalk-listen switch is operated to talk or listen position, respectively,to the input or output of said ampliher and, simultaneously. reverselyconnecting the speaking unit of the selected unit to the output or inputof the amplifier.

10. In a communication system of the class described, a plurality ofdynamic speaking units positioned at spaced apart locations; means ateach of said units for selectively connecting one of said units incommunication with another of said units; an amplifier having an inputand an output; a talk-listen switch at each of said units having a talkposition and a listen position; means for connecting said amplifier tosaid units; a relay switch operable upon movement of a switch at one ofsaid units to talk position and connecting the input of said amplifierwith said unit and the Output of said amplifier with another unit.

11. In a communication system of the class described, a plurality ofdynamic speaking units positioned at spaced apart locations; means ateach of said units for selectively connecting one of said units incommunication with another of said units; an amplifier having an inputand an output; a talk-listen switch at each of said units having a talkposition and a listen position; means for connecting said amplifier tosaid units; a relay switch operable upon movement of a switch at one ofsaid, units to talk position and connecting the input of said amplifierwith said unit and the output of said amplifier with another unit; andmeans operable upon the movement of said talk-listen switch to listen:position for c0nmeeting said unit to the output of said amplifier and,simultaneously connecting another unit to the input of said amplifier.

12. In a communication system of the class described, a plurality ofdynamic speaking units positioned at spaced apart locations: means ateach of said units for selectively connecting one of said units incommunication with another of said units; an amplifier having an inputand an output; a talk-listen switch at each of said units having a talkposition and alisten position; means ously, connecting another unit tothe input of said amplifier; and means operable upon the movement ofsaid switch from listen position to talk position for grounding out theoutput of said 5 amplifier.

RICHARD T. FITZPATRICK.

